<template>
  <section class="todoapp">
    <!-- 除了驼峰, 还可以使用-转换链接 -->
    <TodoHeader
    @addTask='addTaskFn'
    :list='list'
    ></TodoHeader>
    <TodoMain :list='showList' @del='delFn'></TodoMain>
    <TodoFooter 
    @changeType='typeFn'
    @clearTask="clearFn"
    :type='getSel' 
    :len='showList.length'
    ></TodoFooter>
  </section>
</template>

<script>
// 1.0 样式引入
import "./styles/base.css"
import "./styles/index.css"
    
import TodoHeader from "./components/TodoHeader";
import TodoMain from "./components/TodoMain";
import TodoFooter from "./components/TodoFooter";


export default {
  components: {
    TodoHeader,
    TodoMain,
    TodoFooter,
  },
  data() {
    return {
      list: JSON.parse(localStorage.getItem('todolist')) || [],
      getSel:`all`,//表示显示全部，yes已完成，no未完成
    }
  },
  computed:{
    showList(){
      if(this.getSel === `yes`){
        return this.list.filter(item => item.isDone)
      } else if (this.getSel === `no`){
        return this.list.filter(item => !item.isDone)
      }else {
        return this.list
      }
    }
  },
  methods:{
    addTaskFn(task){
      // console.log('addTaskFn',task);
      this.list.push({
        id: this.list.length ? this.list.at(-1).id + 1 : 100,
        name: task,
        idDone: false
      })
    },
    delFn(id){
      this.list = this.list.filter(item => item.id !== id)
    },
    typeFn(type){
      this.getSel = type
    },
    clearFn(){
      // console.log('清除完成');
      this.list = this.list.filter(item => !item.isDone)
      
    }
  },
  watch:{
    list:{
      deep:true,
      handler(){
        localStorage.setItem('todolist',JSON.stringify(this.list))
      }
    }
  }
};
</script>